Brake help please

[jann71]

Hello

Checking bike over before a wee run tomorrow and remembered slight issue with back brake which I need to fix but need some help.
This is difficult to explain. The back wheel is lined up in the centre, when I move the brake where it attaches to the frame it moves to the left, I move it back to centre and it goes left again. Tension in the cable seems ok too.

Does it need tightened behind the brake where it attaches to the frame?

 

[PoweredByVeg]

Yeah, you need to tighten the recessed nut with a 5mm allen key

 

[jann71]

Yeah, you need to tighten the recessed nut with a 5mm allen key

Thanks